[2PS-086]
Large-scale thermo- and mechanosalient martensitic actuation through cooperative twist elasticity in a dense crystal lattice
발표자황경태 (한국과학기술연구원)
연구책임자박상규 (한국과학기술연구원)
Abstract
Martensitic molecular crystals have attracted considerable attention for smart devices such as soft robotics, and MEMS, due to their ultrafast and reversible structural transformations triggered by heat or mechanical force. Nevertheless, the underlying mechanisms and design principles remain insufficiently understood. Here, we present the first example of solid-state twist elasticity in a DDDCS [(2Z,2'Z)-2,2'-(1,4-phenylene)bis(3-(4-(dodecyloxy)phenyl)acrylonitrile)]. DDDCS features three polymorphs (B, Y, and C-phases) that undergo reversible transitions upon thermal and mechanical stimulation. In particular, the Y→B transformation involves a cooperative twist of molecules and a packing motif shift from π-stacking to μ-herringbone, resulting in a 29% crystal elongation. The large deformation is enabled by the flexibility and dipolar interactions of the molecule. This insight suggests a new design principle for high-strain responsive molecular crystal.